Seroprevalencia de Trypanosoma cruzi en niños de Veracruz, México: línea de base epidemiológica para un modelo de control fundamentado en la transmisión activa de la enfermedad de Chagas

Introduction. In 2021 the Ministry of Health of Mexico and the Pan American Health Organization launched an initiative to interrupt intra-domiciliary vector transmission of Chagas Disease (CD), based on knowledge of the prevalence of this disease in children. The Mexican State of Veracruz was the leading of this initiative.Objective. To estimate the seroprevalence of Trypanosoma cruzi infection among children under 15 years of age from rural areas of Veracruz, Mexico.Materials and methods. Eight priority localities from the Municipality of Tempoal, Veracruz, were identified for baseline serology. Blood samples were collected on filter paperfrom 817 individuals (June-August 2017) for screening using a third-generation enzyme immunoassay. Reactive cases were confirmed by indirect hemagglutination (HAI), Enzyme linked immunosorbent assay (ELISA), and indirect immunofluorescence (IIF) tests with peripheral blood serum samples. Seroprevalence and its 95% confidence interval (95% C.I.) were calculated.. Results. In the localities Citlaltepetl, Cornizuelo, Cruz de Palma y Rancho Nuevo, CD cases were confirmed in children under 15 years of age with a seroprevalence of 1,9% (95% C.I.: 1,12-3,16%). Conclusions. These results indicate that these communities present recent transmission of CD and allow establishing an epidemiological baseline for the design and implementation of a model based on activities focused on geographic areas with active transmission to advance towards the elimination of intra-domiciliary vector transmission of CD in Mexico.Introducción. En 2021 la Secretaría de Salud de México y la Organización Panamericana de la Salud lanzaron una iniciativa para la interrupción de la transmisión vectorial intradomiciliaria de la enfermedad de Chagas (EC), fundamentada en el conocimiento de la prevalencia de esta enfermedad en población infantil. El estado mexicano de Veracruz fue punta de lanza de esta iniciativa.Objetivo. Estimar la seroprevalencia de infección por Trypanosoma cruzi en menores de 15 años de localidades rurales de Veracruz, México.Materiales y métodos. Se identificaron 8 localidades prioritarias para la serología basal en el municipio de Tempoal, Veracruz. Se colectaron muestra de sangre en papel filtro de 817 individuos (junio-agosto de 2017) para su tamizaje usando un inmunoensayo enzimático de tercera generación. Los casos reactivos del tamizaje se confirmaron mediante pruebas de hemaglutinación indirecta (HAI), ensayo por inmunoabsorción ligado a enzimas (ELISA) e inmunofluorescencia indirecta (IFI) en muestras de suero colectadas en tubo. Se calculó la seroprevalencia y su intervalo de confianza del 95% (I.C. 95%).Resultados. En las localidades Citlaltépetl, Cornizuelo, Cruz de Palma y Rancho Nuevo se confirmaron casos de la EC en menores de 15 años con una seroprevalencia de 1,9% (I.C. 95%: 1,12-3,16%).Conclusiones. Los resultados indican que estas comunidades presentan transmisión reciente de la EC y permiten establecer una línea de base epidemiológica para el diseño e implementación de un modelo fundamentado en acciones dirigidas a áreas geográficas con transmisión activa para avanzar hacia la eliminación de transmisión vectorial intradomiciliar de la EC en México

Frecuencia de prolongación del intervalo QTc en adultos infectados con VIH de Paraguay en 2020

Introduction: the prolonged QTc interval predisposes to serious arrhythmias. Various medications, including antiretrovirals, can prolong it. The objectives were to determine the demographic, clinical characteristics and the frequency of the prolonged QTc interval in patients with HIV. Methods: we conducted a prospective, observational study with a control group. Men and women, over 18 years of age, with HIV infection, who attended the National Hospital (Itauguá, Paraguay) during 2020, were included. Medical students acted as a control group. All subjects who did not give their consent and those with arrhythmias were excluded. Demographic, clinical, laboratory variables and 12-channel electrocardiogram at rest were measured. The study was approved by the Ethics Committee of the Universidad Privada del Este (Paraguay). Results: 39 HIV patients and 39 healthy controls entered the study. The mean age of the cases was 37 ± 11 years, being 59% male. The most frequent comorbidity in the cases was obesity (7.6%). The mean values ​​of urea, creatinine, K, Ca and Mg in the cases were in the normal range. Prolonged QTc was detected in 18% of the cases and in 0% of the controls. The subjects with the electrocardiographic alteration were all on antiretroviral and multiple antibiotic treatment known to be associated with prolonged Qtc. Conclusion: the frequency of prolonged QTc in HIV patients was 18% and in healthy controls it was 0%. Regular monitoring of the electrocardiogram is recommended in HIV patients receiving drugs that prolong the QT interval.Introducción: el intervalo QTc prolongado predispone a arritmias graves. Diversos medicamentos, entre ellos los antirretrovirales, pueden prolongarlo. Los objetivos fueron determinar las características demográficas, clínicas y la frecuencia del intervalo QTc prolongado en pacientes con VIH. Métodos: estudio observacional, prospectivo, con grupo control. Se incluyeron varones y mujeres, mayores de 18 años, portadores de infección por VIH, que acudieron al Hospital Nacional (Itauguá, Paraguay) durante 2020. Actuaron como grupo control los estudiantes de Medicina. Se excluyeron todos los sujetos que no dieron su consentimiento y los portadores de arritmias. Se midieron variables demográficas, clínicas, laboratoriales y electrocardiograma de 12 canales en reposo. El estudio contó con la aprobación del Comité de Ética de la Universidad Privada del Este (Paraguay). Resultados: ingresaron al estudio 39 pacientes con VIH y 39 controles sanos. La edad media de los casos fue 37 ± 11 años, siendo 59% del sexo masculino. La comorbilidad más frecuente en los casos fue la obesidad (7,6%). Los valores medios de urea, creatinina, K, Ca y Mg en los casos se hallaban en rango normal. Se detectó 18% de QTc prolongado en casos y 0% en los controles. Estos sujetos con alteración electrocardiográfica se hallaban todos en tratamiento antirretroviral y antibiótico múltiple de conocida asociación con QTc prolongado. Conclusión: la frecuencia de QTc prolongado en pacientes con VIH fue del 18% y en controles sanos fue del 0%. Se recomienda el control periódico del electrocardiograma en pacientes con VIH en tratamiento con fármacos que prolongan el intervalo QT

Structural Stability and Electronic Properties of Boron Phosphide Nanotubes: A Density Functional Theory Perspective

Based on the Density Functional Theory (DFT) calculations, we analyze the structural and electronic properties of boron phosphide nanotubes (BPNTs) as functions of chirality. The DFT calculations are performed using the M06-2X method in conjunction with the 6-31G(d) divided valence basis set. All nanostructures, (n,0) BPNT (n = 5–8, 10, 12, 14) and (n,n) BPNT (n = 3–11), were optimized minimizing the total energy, assuming a non-magnetic nature and a total charge neutrality. Results show that the BPNT diameter size increases linearly with the chiral index “n” for both chiralities. According to the global molecular descriptors, the (3,3) BPNT is the most stable structure provided that it shows the largest global hardness value. The low chirality (5,0) BPNT has a strong electrophilic character, and it is the most conductive system due to the small |HOMO-LUMO| energy gap. The chemical potential and electrophilicity index in the zigzag-type BPNTs show remarkable chirality-dependent behavior. The increase in diameter/chirality causes a gradual decrease in the |HOMO-LUMO| energy gap for the zigzag BPNTs; however, in the armchair-type BPNTs, a phase transition is generated from a semiconductor to a conductor system. Therefore, the nanostructures investigated in this work may be suggested for both electrical and biophysical applications

Structural Stability and Electronic Properties of Boron Phosphide Nanotubes: A Density Functional Theory Perspective

Based on the Density Functional Theory (DFT) calculations, we analyze the structural and electronic properties of boron phosphide nanotubes (BPNTs) as functions of chirality. The DFT calculations are performed using the M06-2X method in conjunction with the 6-31G(d) divided valence basis set. All nanostructures, (n,0) BPNT (n = 5–8, 10, 12, 14) and (n,n) BPNT (n = 3–11), were optimized minimizing the total energy, assuming a non-magnetic nature and a total charge neutrality. Results show that the BPNT diameter size increases linearly with the chiral index “n” for both chiralities. According to the global molecular descriptors, the (3,3) BPNT is the most stable structure provided that it shows the largest global hardness value. The low chirality (5,0) BPNT has a strong electrophilic character, and it is the most conductive system due to the small |HOMO-LUMO| energy gap. The chemical potential and electrophilicity index in the zigzag-type BPNTs show remarkable chirality-dependent behavior. The increase in diameter/chirality causes a gradual decrease in the |HOMO-LUMO| energy gap for the zigzag BPNTs; however, in the armchair-type BPNTs, a phase transition is generated from a semiconductor to a conductor system. Therefore, the nanostructures investigated in this work may be suggested for both electrical and biophysical applications